Patient specific electrode location after CI surgery

Introduction:

Cochlea-Implants (CI) give the possibility to restore hearing with deafness or severe hearing loss. Actual studies show that the hearing performance depends on the covered cochlea length. In our presented study we thereby investigated if indication ranges for selected arrays can be derived.

Material and Methods:

In a single center, retrospective study of 350 patients, with a MED-EL FLEX electrode, the individual cochlea geometry (length, number of turns, high and spiral profile) and the electrode location (insertion depth, insertion angle, covered cochlea length) was analyzed.

Results:

The study shows a normal deviation of cochlea length (29 – 45 mm). Because the array-length is predetermined the coverage of the cochlea (in percentage) depends von the individual anatomy (FLEX 20 56%, FLEX 24 68%, FLEX 28 76%). The correlation between insertion depth, covered length and coverage was used to determine indication ranges for selected arrays.

Conclusion:

The results prove that postoperative electrode location depends on the patient specific anatomy. The derived indication ranges supports the surgeon in the preoperative preparation and allow a patient-individual treatment. Linked with audiological data these results can be used to forecast the postoperative outcome (electrode location, speech performance).

Publication History

Publication Date:
18 April 2018 (online)